Multi instance setting ignored when default verb is parsed.

Beginne damit, das Problem mit dem bereitgestellten ParseArguments- und MapResult-Beispiel zu reproduzieren, insbesondere mit argTest5, und verfolge, wie das Standardverb bei aktiviertem AllowMultiInstance geparst wird. Als erledigt gilt die Aufgabe, wenn das Standardverb wiederholte Optionswerte akzeptiert, ohne die Option als mehrfach definiert zu melden, während die anderen Beispiele weiterhin korrekt geparst werden.

Describe the bug
When using the function "MapResult" to parse multiple verbs, the parser ignores the setting "AllowMultiInstance" while parsing the default verb.

Lib version: 2.9.1
Language: C#

To Reproduce
Test the following demo code to see the result.

Demo Class Options:

    [Verb("log", isDefault:true, HelpText = "Log command")]
    class LogOptions
    {
        [Option('a', HelpText = "Option A for log command")]
        public IEnumerable<string> OptionA { get; set; }

        [Option('b', HelpText = "Option B for log command")]
        public IEnumerable<string> OptionB { get; set; }
    }

    [Verb("save", HelpText = "Save command")]
    class SaveOptions
    {
        [Option('d', HelpText = "Option D for save command")]
        public IEnumerable<string> OptionD { get; set; }

        [Option('e', HelpText = "Option E for save command")]
        public IEnumerable<string> OptionE { get; set; }
    }

Demo code:

        Parser parser = new(x =>
        {
            x.HelpWriter = Console.Out;
            x.IgnoreUnknownArguments = true;
            x.AllowMultiInstance = true;
            x.AutoHelp = true;
        });

        var argTest1 = "log -a valueA -b valueB" .Split(' ');  // This works.
        var argTest2 = "save -d valueD -e valueE".Split(' ');  // This works.
        var argTest3 = "-a valueA -b valueB".Split(' ');       // This works.
        var argTest4 = "log -a valueA -b valueB -b valueB2".Split(' '); // This works.
        var argTest5 = " -a valueA -b valueB -b valueB2".Split(' ');     // This don't work.


        var res = parser.ParseArguments<LogOptions, SaveOptions>(argTest5).MapResult(
        (LogOptions opts) => ProcessLogCommand(opts),
        (SaveOptions opts) => ProcessSaveCommand(opts),
        errs => 1);
    }

When trying to parse argTest5 this error is shown:

  ERROR(S):
    Option 'b' is defined multiple times.
  
    -a           Option A for log command
  
    -b           Option B for log command
  
    --help       Display this help screen.
  
    --version    Display version information.

Expected behavior
Option "SaveOptions" correctly parsed with multiple arguments for argument b.